PVC pipe production operation manual

1. Purpose ：Ensure the PVC pipe production operation under the normal  regulation method & ensure the products  quality .

2. application :PVC  pipe  production  line  and other similar plastic products production

3. operate manual ：

A. Install or replace the required molds, qualitative molds, sealing baffles, cutting machine fixtures, cutting length devices, and all parts that need to be connected according to the production plan.

B. Connect and check each heater/coil and thermocouple, and then heat them in three stages (80 degrees for the first stage, 120 degrees for the second stage, and the required production temperature for the third stage). While heating, observe whether the heater (coil) and auxiliary equipment are running normally.

C. The barrel and mold must be fully heated. Large product molds require heating for about 2-3 hours, while small product molds require heating for about 2 hours. Maintain insulation while preparing for startup; For example, foreign objects in the hopper, vacuum eye of the machine barrel, and other material channels should be promptly removed, and the materials required for production and some shutdown materials should be prepared.

D. After the temperature reaches the set temperature and is kept warm, check whether the connecting screws have loosened due to different materials and inconsistent thermal expansion coefficients, and then tighten them again. After adding the materials to be produced into the hopper, turn on the machine.

E. Set all speed controls to the ‘0’ position, start the synchronous host, and adjust the host speed to operate at low speed (at this time, the host screw speed should not exceed 5r/min). Depending on the actual situation, slowly add a small amount of shutdown material to prevent the material from carbonizing due to prolonged time before it leaves the mold during slow operation. Then start the auxiliary machine or open the hopper gate for synchronous feeding and ensure speed matching. When adjusting the speed, it should be slowly and smoothly adjusted, otherwise it will cause wear on the screw and material cylinder components due to the instantaneous torque of the rotating system. The torque current of the equipment during operation should not be too high or too low. Different melt pressures and torque currents should be controlled according to different models of extruders, materials, or formal operation manuals, and overloading operation is not allowed.

F. When the material has not been extruded through the mold mouth, do not face the front of the mold mouth directly, as sometimes the material may spray out and cause injury due to other reasons. After the material is extruded through the mold mouth, observe the vacuum hole of the main machine barrel and the plasticization status of the extruded material at the mold mouth at any time. When the material is semi plasticized in the barrel and combined with the torque current of the main engine, turn on the main engine vacuum system. Do not use metal tools to poke the material to prevent damage to the equipment. The vacuum degree should be around 0.03-0.05M pa, and observe the color and plasticization status of the material extruded from the mold mouth. When the plasticization is good, product production can be carried out.

G. After passing the well plasticized materials through the shaping cooling table (box), the traction machine device is used for automatic traction cutting. When the material is not fully formed, the power supply of the cutting machine needs to be turned off, otherwise it may damage the blades due to the mismatch of the cutting machine fixture. After the material is fully formed, turn on the power of the cutting machine and adjust each link of the entire production line according to the production plan to achieve automatic continuous production.

H. During normal production, the temperature of the barrel and die must be set according to the process requirements, and any changes should be observed at any time. If any abnormalities are found, they should be stopped immediately, and the cause should be identified and dealt with by oneself or reported to the person in charge. Only after troubleshooting can the device be turned on, and abnormal operation is strictly prohibited.

I. Adjust the traction speed, center distance of the shaping box (table), and mold adjustment screws based on the specifications, models, shapes, etc. of the produced products, and check the changes in the appearance, inner wall, cross-sectional wall thickness, length, and cutting end face of the products to ensure that the products meet the standard requirements.

J. The product should be completely cooled in the vacuum cooling jacket (box), and the vacuum degree inside the water jacket (box) should be appropriate to achieve precise sizing. If the product still hasn’t cooled properly when it comes out of the cooling jacket (box), it needs to be watered, soaked for cooling, or the auxiliary cooling water tank needs to be turned on.

K. It is necessary to ensure the cleanliness of the circulating water. No debris is allowed to be placed in the shaping groove to prevent water pollution. Regularly maintain the cleanliness and hygiene of the production line and surrounding environment.

L. Do a good job in handover work. The previous shift should explain the equipment operation status and precautions clearly to the next shift.

M. Make good production records and equipment operation records. It is recommended to record every 2 hours and carefully fill in the “Equipment Operation Process Record Form”.

N. Before the production plan is completed, pre prepared shutdown materials should be added according to whether the mold needs to be disassembled. The feeding device should be lowered in sequence, and a small amount of shutdown materials should be slowly added. Unnecessary auxiliary machines should be stopped, and the feeding device should be stopped. After using the shutdown materials to squeeze all the production materials in the barrel out of the mold mouth, the main machine should be stopped, the temperature should be adjusted, the water, electricity, and gas should be turned off, and the site should be cleaned.